diff --git a/src/main/java/pw/kaboom/commandspy/Main.java b/src/main/java/pw/kaboom/commandspy/Main.java
index 8e7e48c..10692b4 100644
--- a/src/main/java/pw/kaboom/commandspy/Main.java
+++ b/src/main/java/pw/kaboom/commandspy/Main.java
@@ -6,7 +6,6 @@ import org.bukkit.Bukkit;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
-import org.bukkit.command.ConsoleCommandSender;
 import org.bukkit.configuration.file.FileConfiguration;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
@@ -17,6 +16,7 @@ import org.bukkit.event.player.PlayerCommandPreprocessEvent;
 import org.bukkit.plugin.java.JavaPlugin;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
+import org.jetbrains.annotations.NotNull;
 
 public final class Main extends JavaPlugin implements CommandExecutor, Listener {
     private FileConfiguration config;
@@ -44,19 +44,18 @@ public final class Main extends JavaPlugin implements CommandExecutor, Listener
         if (config.contains(player.getUniqueId().toString())) {
             return NamedTextColor.YELLOW;
         }
+
         return NamedTextColor.AQUA;
     }
 
     @Override
-    public boolean onCommand(final CommandSender sender, final Command cmd, final String label,
-                             final String[] args) {
-        if (sender instanceof ConsoleCommandSender) {
+    public boolean onCommand(final @NotNull CommandSender sender, final @NotNull Command cmd,
+                             final @NotNull String label, final String[] args) {
+        if (!(sender instanceof final Player player)) {
             sender.sendMessage(Component.text("Command has to be run by a player"));
             return true;
         }
 
-        final Player player = (Player) sender;
-
         if (args.length >= 1 && "on".equalsIgnoreCase(args[0])) {
             enableCommandSpy(player);
             return true;
@@ -78,31 +77,32 @@ public final class Main extends JavaPlugin implements CommandExecutor, Listener
             .append(Component.text(": "))
             .append(Component.text(event.getMessage()));
 
-        for (String uuidString : config.getKeys(false)) {
+        for (final String uuidString : config.getKeys(false)) {
             final UUID uuid = UUID.fromString(uuidString);
             final Player recipient = Bukkit.getPlayer(uuid);
 
             if (recipient == null) {
                 continue;
             }
+
             recipient.sendMessage(message);
         }
     }
 
-    @EventHandler
+    @EventHandler(ignoreCancelled = true, priority = EventPriority.MONITOR)
     void onSignChange(final SignChangeEvent event) {
         final Player player = event.getPlayer();
         final NamedTextColor color = getTextColor(player);
         Component message = Component.text(player.getName(), color)
             .append(Component.text(" created a sign with contents:"));
 
-        for (Component line : event.lines()) {
+        for (final Component line : event.lines()) {
             message = message
                 .append(Component.text("\n "))
                 .append(line);
         }
 
-        for (String uuidString : config.getKeys(false)) {
+        for (final String uuidString : config.getKeys(false)) {
             final UUID uuid = UUID.fromString(uuidString);
             final Player recipient = Bukkit.getPlayer(uuid);